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The 20p Test

Ellie Dyer-Brown, 2 months ago

3 min read

  • Advice
  • News
Source: TyreSafe

WhoCanFixMyCar explains how you can check your tyre tread depth using a 20p coin - and avoid a hefty fine of up to £2,500!

If you’re anything like us, you probably have a handful of loose change lurking somewhere in your car, be it in the cupholder or lost under the seats. The good news is that shrapnel like this - and twenty pence pieces in particular - which might otherwise go unused could actually come in handy for checking your tyre tread. How, we hear you ask? Read on to find out!


How to do the 20p test

Simply place a twenty pence piece into the main tread grooves of the tyre you want to check. If the outer band is obscured when it’s inserted, then the tyre is above the legal limit and can continue to be used. However, if the outer band is visible, this suggests that the depth is insufficient and your tyres are therefore illegal.

When you carry out the 20p test, you should check three separate places on each tyre as sometimes they can wear unevenly. It’s a good idea to do this once every month.

This quick and easy but ingenious hack saves you from having to purchase a tread gauge - all you have to do is keep a twenty pence coin in your car to use again and again.


What does the law say about tread depth?

UK law states that the minimum tyre tread depth on cars is 1.6mm across the central three quarters of the tread, around the entire circumference of the tyre.


Why is tread depth important?

The grooves you find on your tyres play an important role in removing water from the surface of the road, allowing for better grip. If your tyres had no treads, you’d seriously struggle to control your car.

The deeper the tread depth, the more effective the tyre at clearing water from the road surface. This results in shorter stopping distances, which ultimately means you’re a lot safer when you get behind the wheel.


In the event that you carry out the 20p test and find that the tread on your tyres is lacking, there’s no need to panic. You can compare car tyre fitting prices from reliable local garages using WhoCanFixMyCar. 

Did you know that drivers save an average of £44.93 on tyre fitting booked through WhoCanFixMyCar?

Alternatively, why not try out our network of excellent mobile mechanics who will come straight to you to do the job.

Whichever tyre fitting method you choose, it’s important to replace worn tyres as soon as possible to avoid being caught on the wrong side of the law, or you could end up with a hefty fine of up to £2,500 and three points on your license per tyre. So act fast!